Addendum to the American Megatrends Atlas VIP Motherboard User's Guide 8/17/94 Please make the following corrections and additions to this manual: Delete all references to 100 MHz. This motherboard supports the 90 MHz Pentium CPU. Delete all references to a built-in battery. This motherboard must use a 4.5V external battery. Page 3 Cache Memory Replace the sentence about Data SRAM with the following: The Data SRAM is 3.3V 15 ns 32 KB x8 SRAMs. You must use only 3.3V SRAMs when upgrading the L2 secondary (external) cache memory on this motherboard. Page 6 Interrupt Levels Delete the last sentence before the table and replace with: If IRQ 5, 9, 10, 11, or 15 is used by a VL-Bus or ISA bus device, set the corresponding IRQ option in Chipset Setup to ISA. Then this IRQ will not be allocated to any PCI device. Page 21 J43 Set CPU Speed Leave J43 OPEN always. Page 22 J19 and J21 J19 and J21 must always be OPEN. Page 22 J24 Heading The third line contains J51. It should be J24. Atlas VIP Motherboard Addendum, Continued Page 27 Delete Last Sentence and Add: PS3 is the 3.3V power connector. If a PCI adapter card that requires 3.3V is installed, use a power supply that provides 3.3V and connect the 3.3V power supply cable to PS3. The PS3 pinout is on page 29. Page 33 J46 J46 can be used to attach to the turbo LED or to a power on LED. This motherboard always operates in turbo mode. Page 34 External Battery Connector Delete all reference to an onboard battery. J7 must be connected to a 4.5 volt external battery. Page 43 PCI Slot Numbers The correct numbers are: PCI slot IDSEL Device Number 1 19 8 2 18 7 3 17 6 Page 50 Add the following after WINBIOS Setup: You must load the Optimal default settings the first time that you run WINBIOS Setup. Pages 44 and 70 NCR PCI SCSI BIOS WINBIOS automatically detects offboard PCI devices that need the NCR SCSI BIOS and automatically supplies the SCSI BIOS to them. Page 68 DRAM Region A Change all references to DRAM Region A to DRAM Region B. Atlas VIP Motherboard Addendum, Continued Page 70 PCI IRQ Option Delete this option. Page 70 PCI IDE Card Present In This option concerns any offboard PCI IDE controller installed in the computer. The onboard mode 3 IDE controller is on the VL-Bus. If an offboard IDE controller on the PCI bus is installed, the onboard IDE controller cannot be used and vice versa. This motherboard supports up to two IDE drives. Page 71 PCI IDE IRQ option This option concerns any offboard PCI IDE adapter card. This option must be set to Edge when an offboard PCI IDE controller is used. Page 72 Onboard IDE The settings for this option are En-Pri (enable the primary IDE drive) or Disabled. The En-Sec option is invalid. Pages 72-73 Serial Port FIFO The serial port FIFO buffers cannot be configured via WINBIOS Setup. Delete the Serial Port 1 FIFO and Serial Port 2 FIFO Peripheral Setup options. The serial port FIFO buffers may be used, but they are strictly under the control of any software that can use these buffers. Page 73 IDE Block Mode Add the following: Do not enable the IDE Block Mode option unless you are certain that the IDE drive installed in the computer supports IDE block mode. Atlas VIP Motherboard Addendum, Continued Page 73 32-Bit Transfer This option must be set to Disabled when an offboard ISA IDE controller is used. Page 74 IDE LBA Mode Add the following: Do not enable the IDE LBA Mode option unless you are certain that the IDE drive installed in the computer supports IDE LBA mode. A drive formatted without LBA should not be used when LBA mode is enabled. Page 74 IDE 0 Transfer Mode IDE 1 Transfer Mode The Auto setting for these two options does not work with some older IDE drives. Some older IDE drives do not return the correct IDE mode to WINBIOS, so you must not use the Auto setting. These older IDE drives must be set to Mode 0. Page 87 Airflow on the CPU The OEM must mount this motherboard in a chassis that has a fan that blows air over the CPU to ensure proper CPU cooling. Proper airflow is critical for reliable operation of this motherboard.